Photometers and other instruments for detecting and measuring absorption or emission of light from a test sample can be useful measures of chemical and biological systems and changes, particularly in the determination of emitted light from test samples containing luminescent components.
There are a number of photometers for the measurement of light emission, wherein the test sample, whose light is to be determined, can be maintained at an acceptable optical temperature or other required conditions. Such a photometer usually requires a shutter assembly for sealing a test sample in the photometer, and a photosensitive device for the determination of the emitted light from the test sample. The assembly usually comprises a body having a sample chamber and a light path opening from the sample chamber to the photosensitive device. The body includes a means of mounting the sample chamber in relationship to the photosensitive device for the detection of the light transmitted from the sample chamber.
The assembly also requires a shutter assembly comprising an opaque housing to shield the photosensitive device from light transmitted from the sample chamber when in the closed position. Typically, the housing has an aperture for the communication between the photosensitive device, which may be a photomultiplier tube, and the light path from said sample chamber when the shutter is in an open position. A shutter or other means must be provided for securely closing the sample chamber to prevent the interference of external light when the device is in operation. One type of photometer for detecting and measuring luminescence in test materials is disclosed, for example, in U.S. Pat. No. 4,213,703, issued Jul. 22, 1980, entitled "Photometer with Stationary Sample Holder and Rotatable Shutter".
Photometer analyzers are typically included for use with multiple bioluminescent or chemiluminescent assay tests. One analyzer, known as a "Luminator.RTM." (a trademark of Charm Sciences, Inc., of Malden, Mass.), is a portable analyzer which is adapted to detect emitted light and to interpret test assay results, and works in conjunction with a varying number of sample holders to determine and measure the presence of ATP, pesticides, phosphatase, and somatic cells; predict shelf life; and also to conduct general microbial quality tests for a wide variety of products. The device is capable of storing and sorting assay data in its memory, and transferring information to a display panel or printer or a computer system. The device also allows for on-site sample testing and for hard copy printouts or copy data management of test results at another location and time.
The analyzer is typically powered by a rechargeable, e.g. Lithium, battery pack or an AC-DC power supply. The Luminator.RTM. device includes a sample chamber with a turret having an entrance port, into which a test vial containing the test sample to be determined is inserted, and then the turret is rotated to a closed position to block external light from interfering with the photometer analysis. The turret is high positioned on the external top surface of the housing, typically to a clearance of at least 1/2 inch, in order to provide for a light-blocking seal, as allowing light into the sample chamber during the testing procedure would interfere with the test results. When the test results have been determined, the turret is rotated to the open position and the test sample vial removed.
The analyzer provides a user with the light emission count, in relative light units (RLU), of a test sample. The Luminator.RTM. photometer analyzer and its operation is described in greater detail in Charm's "Luminator-K Operating Instructions" Bulletin, (.COPYRGT.1995 by Charm Sciences, Inc., Malden, Mass.), hereby incorporated by reference.
Generally, the test vial containing the sample employed in the test sample holder is a transparent or translucent vial, which permits the passage or emission of the emitted exposed light, for example, in a bioluminescent assay, and, for example, permits light transmission of from about 300 to 650 nanometers, which is visible light range. The test vial with the test sample therein may be separately inserted, or may be removed as a detachable component of a separate test sample holder device, such as an elongated tube, for example, a Pocketswab.RTM. device, (a registered trademark of Charm Sciences, Inc., of Malden, Mass.). The test vial with the test sample may be threadably removed from one end of the test sample holder and inserted as a separated test vial into the sample chamber, and then the sample turret closed.
One plastic, molded, test sample holder device is described in U.S. patent application Ser. No. 08/619,586, now U.S. Pat. No. 5,827,675, issued Oct. 27, 1998, (the National Phase, entered Mar. 26, 1996), of PCT application PCT/US96/00524, filed Jan. 2, 1996, and U.S. Design patent application Ser. No. 29/052,316, filed Apr. 2, 1996, now U.S. Pat. No. D.388,519, issued Dec. 30, 1997 both hereby incorporated by reference.
While such prior art photometers and test sample holders and methods are useful, it is desired to provide for an improved photometer analyzer with a reduced size sample chamber, without sacrificing the efficiency and performance of the photometer and the light blocking capability of the turret, and to provide a new and improved test sample holder suitable for use with the photometer.